One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,7)(4,8)(5,6)(9,10)(11,15)(12,14)(13,16) involution — undirected(9,11)(10,13)(12,16)(14,15)(17,18,21,25)(19,26,29,31)(20,23,27,24)(22,30,32,28)(2,6)(7,8)(10,14)(11,16)(17,19,27,30,21,29,20,28)(18,22,23,31,25,32,24,26)(1,3,5,4)(2,7,6,8)(10,14)(13,15)(17,20,21,27)(18,23,25,24)(19,28,29,30)(22,31,32,26)(1,4,5,3)(2,8,6,7)(17,19,20,28,21,29,27,30)(18,22,24,26,25,32,23,31)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.